Proportional divider



Nov. 3, 1942. w. L. MORGAN PROPORTIONAL DIVIDER Original Filed March 9.19:52 2 Sheets-Sheet l anonwq gww'nkw W. L. Marya.

Nov. 3, 1942. w. MORGAN PROPORTIONAL DIVIDER Original Filed March 9,1952 2 Sheets-Sheet 2 Patented Nov. 3, 1942 PROPORTIONAL DIVIDER WalterL. Morgan, Phoenix, Ariz.

Substituted for abandoned application Serial No. 597,776, March 9, 1932.This application March 12, 1942, Serial No. 434,448

Claims.

.This invention relates to a proportional divider, sub-divider, contourline interpolater or contour meter and generally aims to provide amechanical means operable to accurately divide a given'line into anygiven number of equal parts, or determine the regular contour intervals,and in any instance where fractional parts of a unit are required at oneor both ends of the given distance, same can be accurately determined.The instrument is of such character that it may be used generally in thedrafting room for other purposes, such as a parallel line ruler, drawingconcentric lines, cross-hatching, shading, arc scribing and the like,and one in which angles can be determined with the instrument itself anddispense with the requirement of a protractor to be used therewith.

This application .is a substitute for my prior abandoned applicationfiled March 9, 1932, Serial Number 597,776, and allowed July 19, 1933.

' The more specific objects and advantages will become apparent from aconsideration of the description following taken in connection withaccompanying drawings illustrating an operative embodiment.

In said drawings:

Figure 1 is a plan view showing the invention in use,

Figure 2 is an enlarged plan view of the invention taken fromthe reverseside of Figure 1 with the slides changed in position,

Figure 3 is an edge elevation of the same,

Figure 4 is a partial plan and section showing the scale slide and itsconnection to the bar,

Figure 5 is a cross sectional View taken on the line 55 of'Figur 4,

LF'igureG is a cross sectional view taken on the line 65 of Figure 4,

Figure '7 is a fragmentary view partly in section and partly inelevation, showing the connection between the second slide and the bar,

Figure 8 is a cross sectional view taken on the line 8-8 of Figure 7,

Figure 9 is a plan View of one of the slides,

Figure 10 is an end view of the slide of Figure 9, and

Figure 11 is a plan View of the slide carrying the scale arm.

Referring specifically to the drawings, the invention comprises a bar IUof any suitable material such as wood, metal, xylonite of the like, uponwhich a number of scales, A, B, C, D, and E are delineated, which scalesbegin at a common line or zero. The scales mentioned occur on one sideof the bar While the reverse side is also graduated with scales butpreferably for larger units, and being designated A, B, C, D, and E. Thelongitudinal edges of the bar 10 are provided with grooves ll toaccommodate the mounting of slides l2 and I3. Slide 13 consists of barsor strips [4 having tongues I! extending into the grooves I and whichbars are connected by a transparent sheet 16, for instance of Celluloid.Slide 12 consists of strips or bars I! having tongues l8 disposed in thegrooves II and which bars are connected by a sheet I9 of Celluloid orthe like. A suitably graduated scale arm 20 is pivoted at 2[ to one ofthebars I4 and therear surface thereof is flushed with adjacent surfaceof the bar l0 and the bolt 2| is also flush with the latter surface. Asaresult, the bar l0 and arm 29 may rest flat on a drawing board, paper orsupporting surface. Also when the device is not in use or is packed, thearm 29 will engage with and be parallel to one edge of the bar Ii], inwhich position it may be fastened by the bolt 2|. The ruling edge of thearm 20 passes through the center of the pivot 2|.

In order to frictionally hold the slidesin different adjusted positionsalong the bar Ill, one of the tongues l5 and one of the tongues I8 maybe a metallic spring as shown.

The sheets or faces lfi and IQ of theslides have index lines 33 and 34,which extends across all of the scales of the bar I ll. subdivided unitsof the several scales of bar [8, are graduated on thesheets l6 and 19 asshown but extends in O posite directions asat 35 and 35. Said index1ines 33 and 34 are as near as practical to the inner edges of thesheets 16 and H] in order that reading withthe two slides may be madenear eachother. On one bar l! of the slide l2, a pointer 31 is provided,the end of which ter- 4 minates on a line running parallel to the bar [0and passing through the pivot point 2|.

Any suitable means may be used on the slide to indicate the particularscale being used at each setting or a color scheme may be used for thesame purpose in connection with the various One use of the device issuggested in Figure 1. After the elevations in the notes made from thefield survey are potted according to the field measurements, theinstrument is used. To this end, first draw a light pencil lineconnecting any two points of elevation between which the even footcontour intervals are to be determined. In the example illustrated, thedifference in elevation is say 50 feet, at five foot contour intervals,hence there would be ten spaces and inasmuch as these elevations end in5, (or 0), the index line and pointer of slide l2 can be set at 0-0 onthe bar It). Then place the instrument in any convenient position withthe pointer 31 on elevation 1385 as shown in Figure 1, and thereuponselect the scale with 10 units nearest corresponding to the horizontaldistance between the.

two elevations.

Set the index line of slide [3 on IE] of scale 13 and then swing the arm20 so that the ruling edge will pass through the point at elevation 1935as shown in Figure 1. Clamp arm 2!] in this position and move slide I3to the numerals 9, 8, 7, etc. and draw a line along arm 20 Where thesame intersects the light pencil line connecting elevations 1855 and1935, which intersections are the contour intervals. In the examplegiven scale B was used, but scale C could have been used. The result maybe obtained without moving the instrument.

With the graduations or verniers on sheets [6 and [9, decimal parts ofthe units on the various scales may be determined and after the operatorbecomes familiar with the use of this instrument,

he will find that it will cover the average range of contour-lineinterpolating.

The device is also capable of use as an angle protractor. This isaccomplished by providing arm 20 with a series of lines 3!! adjacent toits rear or upper edge that may be supplied with numeral indicationsarranged progressively outwardly from the pivot 2| as shown in Figure 1,that is 5, 10, 15, and so on to 45 adjacent to the outer end of the arm.Then by securing slide l3 on bar It) at a point thereon that the lineindicatecl 45 will touch pointer 31 when arm 20 is parallel with the barand then fixing the arm at right angles to the different angles may bescribed with a straight edge using pointer 31 and lines 39 as guides forthe straight edge.

Various other uses may be made of the apparatus or instrument andchanges may be resorted to within the spirit and scope of the invention.For instance, the principle used in the device may also be applied to adevice of cylindrical design.

I claim as my invention:

1. An instrument of the class described comprising a bar having scalesthereon, slides movable along the bar having index lines relativelyclose to their inner ends, said slides having scales thereonconstituting subdivided units of the first mentioned scales andextending in opposite directions from the respective index lines.

2. An instrument of the class described comprising a bar having scalesof multiple ratios thereon, slides movable along the bar having indexlines relatively close to their inner ends, said slides having scalesthereon constituting subdividcd units of the first mentioned scales andextending in opposite directions from the respective index lines, and ascale arm pivotally attached to and extending from one of the slides.

3. An instrument of the class described comprising a bar having scalesof multiple ratios thereon, slides movable along the bar having indexlines relatively close to their inner ends, said slides having scalesthereon constituting subdivided units of the first mentioned scales andex tending in opposite directions from the respective index lines, and ascale arm pivotally attached to and extending from one of the slides andhaving one face thereof fiush with one face of the bar whereby the samemay engage a supporting surface, said bar having grooves, tongue meanson the slides engaged in said grooves, said tongue means enabling theslides to be removed and reversed.

l. An instrument of the class described comprising a car having scalesof multiple ratios thereon, slides movable along the bar having indexlines relatively close to their inner ends, said slides having scalesthereon constituting subdivided units of the first mentioned scales andextending in opposite directions from the respective index lines, and ascale arm pivotally attached to and extending from one of the slides andhaving one face thereof flush with one face of the bar whereby the samemay engage a supporting surface, and said bar having a roughened surfaceadjacent opposite ends for the purpose specified.

5. An instrument of the class described comprising a bar having scalesof multiple ratios thereon, slides movable along the bar having indexlines relativel close to their inner ends, said slides having scalesthereon constituting subdivided units of the first mentioned scales andextending in opposite directions from the respective index lines, andthe scale arm pivotally attached to and extending from one of the slidesand having one face thereof flush with one face of the bar whereby thesame may engage a supporting surface, said slides having index linesthereon,

, and one of the slides having a pointer on a line with the pivotal axisof the scale arm of the other slide.

WALTER L. MORGAN.

